The present invention relates to a front-end structure of a motor vehicle.
The following discussion of related art is provided to assist the reader in understanding the advantages of the invention, and is not to be construed as an admission that this related art is prior art to this invention.
During operation, motor vehicles are often exposed to dangers, in particular in the form of collisions. In this case it is possible that motor vehicles collide with other motor vehicles or that a motor vehicle drives onto an obstacle or another fixed item.
For this purpose, crash systems have been developed which are intended to realize two fundamental principles. On one hand the crash system is supposed to protect the occupants of a motor vehicle from the forces acting as a result of the impact and accelerations as best as possible. Thus, a crash system may be configured in order to convert kinetic energy into deformation energy for example by way of a crash box so as to mitigate the impact acceleration acting on the occupants as best as possible.
A further object of the crash system is however to absorb or conduct the damage and deformation caused at the motor vehicle by the accident or the impact in a targeted manner, in particular when only low speeds are involved, so that costs of reconstruction or repair of the motor vehicle can be kept low.
The most common crash structure of a motor vehicle known to date is configured so that a transverse member is arranged on the front on the motor vehicle, and is fixed on the motor vehicle by crash boxes which become deformed in the case of an impact. Mostly, the crash boxes are mounted as an extension of the longitudinal member of the motor vehicle. When a motor vehicle drives onto a fixed obstacle or collides with another vehicle, the bending-stiff transverse member absorbs the force and transmits it to the crash boxes. The crash boxes themselves become deformed for example through the formation of folds, and thus convert a portion of the impact energy into deformation energy.
In a partially overlapping frontal collision, in particular in the case of a partially overlapping frontal collision with less than 25% overlap, however, the problem arises that the impact energy absorbed by the transverse member is not introduced into the longitudinal member via the crash box in a manner that the impact energy can be absorbed. Rather there is the danger that an excessively strong lateral impact will cause the longitudinal member to bend away in the transverse direction of the vehicle thus rendering the crash box incapable of converting the impact energy into deformation energy in the first place.
From the state of the art, a kinematic coupling of the front wheels of the motor vehicle is known through DE 100 32 710 A1 or DE 101 13 098 A1 in which the front wheel of the motor vehicle in case of a crash is respectively pivoted in toe-in position in order to cause the obstacle to laterally slide off relative to the motor vehicle. However, this requires a complex kinematic coupling and limits the design freedom of the wheel suspension.
From EP 1 322 949 A2 a front wheel frame structure for a motor vehicle is further known in which the longitudinal member and the crash boxes do not substantially extend in longitudinal direction of the motor vehicle but are angled at their front ends relative to the longitudinal direction of the vehicle. In addition a subframe is provided which provides the front-end structure with stiffness. Such a system however, adversely affects the crash performance of the motor vehicle in case of a frontal crash, which is more likely during operation of the motor vehicle.
It would therefore be desirable and advantageous to provide a possibility to significantly improve the crash performance of a motor vehicle for a frontal collision with partial overlap without affecting the constructive freedom of the front-end structure and the wheel suspension of the motor vehicle.